JP2015173069A5 - - Google Patents

Description

In the third invention, mass calibration information is not stored for a plurality of collision-induced dissociation gas pressures as in the first and second inventions, but only the mass calibration information related to the collision-induced dissociation gas pressure specified by the user is calibrated. When the target sample is subjected to MS / MS analysis using the collision-induced dissociation gas pressure, mass calibration using the mass calibration information is executed. According to such a configuration, there is an advantage that the amount of mass calibration information to be held can be further reduced. In addition, the “mass calibration information indicating the relationship between the mass-to-charge ratio and the calibration value obtained by performing the analysis involving the dissociation of the precursor ion in the collision cell under the collision-induced dissociation gas pressure specified by the user” is Or “under the collision-induced dissociation gas pressure specified by the user”, and obtained by performing an analysis in one measurement mode specified by the user, or “the collision-induced dissociation specified by the user” It may be obtained by performing analysis in various measurement modes under “gas pressure”. In the former case, the control means reads out the mass calibration information obtained by performing the analysis in the one measurement mode from the calibration information storage means, and drives the front quadrupole and the rear quadrupole based on the information. Shall. On the other hand, in the latter case, the mass calibration information stored in the calibration information storage means describes the relationship between the mass-to-charge ratio and the calibration value for each measurement mode under the “collision-induced dissociation gas pressure specified by the user”. since the objects, the control means reads the mass calibration information corresponding to the measurement mode of the MS / MS analysis performed by the calibration information storage means, respectively drive the front quadrupole and subsequent quadrupole based on the information It shall be.

The triple quadrupole mass spectrometer of the present embodiment includes an ion source 12 for ionizing a sample to be measured and four rod electrodes in an analysis chamber 11 that is evacuated by a vacuum pump (not shown). A front quadrupole mass filter (front quadrupole) 13 and a rear quadrupole mass filter (back quadrupole) 16, a collision cell 14 having a multipole ion guide 15 disposed therein, and ions And a detector 17 that outputs a detection signal corresponding to the amount of ions. The flow path switching unit 10 switches the sample to be measured supplied from, for example, a gas chromatograph (not shown) and the standard sample for calibration / adjustment, and supplies them to the ion source 12. Various compounds such as PEG (polyethylene glycol), TFA (trifluoroacetic acid), and PFTBA (perfluorotributylamine) can be used as the standard sample. When the sample is a gas, an ion source 12 that performs ionization of the sample by an EI (electron ionization) method, a CI (chemical ionization) method, or the like is used. When the sample is a liquid, as the ion source 12 What performs ionization of the sample by atmospheric pressure ionization methods, such as ESI (electrospray ionization) method, APCI (atmospheric pressure chemical ionization) method, and APPI ( atmospheric pressure photoionization ) method, is used. When ionizing a sample by the atmospheric pressure ionization method, the ion source 12 is provided outside the analysis chamber 11, and the ion source 12 is configured not to be evacuated by the vacuum pump. In this case, a solvent removal unit is provided between the ion source 12 and the analysis chamber 11, and ions generated in the ion source 12 are introduced into the analysis chamber 11 through the solvent removal unit.

The control unit 20 refers to the mass calibration table corresponding to the CID gas pressure of 200 kPa in the Q3 scan mass calibration table set 22B2 held in the mass calibration table storage unit 22, and designates the specified scan speed of 2000 u / s. The calibration value corresponding to is read out. That is, the calibration values (−0.79, −0.69, −0.48,...) In the fifth row in the lower table of FIG. Then, the control unit 20 controls the Q3 power supply unit 27 using the read calibration value so that the mass scan in the mass-to-charge ratio range m / z 70 to 1300 is repeated at the scanning speed 2000 u / s in the subsequent quadrupole 16. To.